As the winds came and went along the valley, the tree nodded and swayed-only a little, but that little was enough. With every movement, the tree's root system, which underlay the entire city, tugged and distorted the buried crystalline cliff upon which the city had been founded, as long ago in Lithian pre-history as was the founding of Rome on Earth. At every such pressure, the buried cliff responded with a vast heart-pulse of radio waves-a pulse detectable not only all over Lithia, but far out in space as well. The four Commission members had heard those pulses first on shipboard, when Alpha Arietis, Lithia's sun, was still only a point of light ahead of them, and had looked into each other's faces with eyes gleaming with conjecture.

The bursts, however, were sheer noise. How the Lithians modulated them to carry information-not only messages, but the amazing navigational grid, the planet-wide time-signal system, and much more-was something as remote from Ruiz-Sanchez' understanding as affine theory, although Cleaver said it was all perfectly simple once you understood it. It had something to do with semi-conduction and solid-state physics, which (again according to Cleaver) the Lithians understood better than any Earthman.

A free-association jump which startled him momentarily reminded him of the current doyen of Earthly affine theory, a man who signed his papers "H. O. Petard," though his real (if scarcely more likely) name was Lucien le Comte des Bois-d'Averoigne. Nor was the association as free as it appeared on the surface, Ruiz-Sanchez realized, for the count was a striking example of the now almost total alienation of modern physics from the common physical experiences of mankind. His title was not a patent of nobility, but merely a part of his name which had been maintained in his family long after the political system which had granted the patent had vanished away, a victim of the dividing up of Earth under the Shelter economy. There was more honor appertaining to the name itself than to the title, for the count had pretensions to hereditary grandeur which reached all the way back into thirteenth-century England, to the author of Lucien Wycham His Boke of Magick.